Technical Field
This application relates generally to overlay networking and, in particular, to techniques to accelerate delivery of content (e.g., video) to end users on mobile networks.
Brief Description of the Related Art
Distributed computer systems are well-known in the prior art. One such distributed computer system is a “content delivery network” or “CDN” that is operated and managed by a service provider. The service provider typically provides the content delivery service on behalf of third parties (customers) who use the service provider's infrastructure. A distributed system of this type typically refers to a collection of autonomous computers linked by a network or networks, together with the software, systems, protocols and techniques designed to facilitate various services, such as content delivery, web application acceleration, or other support of outsourced origin site infrastructure. A CDN service provider typically provides service delivery through digital properties (such as a website), which are provisioned in a customer portal and then deployed to the network. A digital property typically is bound to one or more edge configurations that allow the service provider to account for traffic and bill its customer.
Overlay networks platforms such as CDNs provide content acceleration to end user devices that access the public Internet via end user access networks, such as Internet service providers. Mobile device users, however, do not connect to the Internet directly; rather, these devices typically access Internet content via their cellular networks, or via a WiFi network. CDN servers, however, typically are not deployed within the cellular network. Thus, today the CDN edge server closest to the mobile network operator IP gateway (e.g., GGSN (3G-UMTS)/PDSN-HA (3G-CDMA) or PGW (LTE)) is used to accelerate content into the cellular network. As a consequence, typically the experience of viewing certain types of overlay network-delivered content on end user mobile devices is not very satisfactory. In particular, presently mobile device users download content interactively. The CDN delivers what the user requests. Users experience considerable latency when viewing large size content, such as video. The requests often happen during “peak traffic” hours when there is network congestion leading to packet drops and retransmission. This leads to inefficient use of network resources, slow or incomplete loading of content, and low quality of experience. Methods like adaptive bit rate streaming compensate for network congestion by downloading lower quality (low bit-rate) video and hence lower the Quality of Experience (QoE) even further.
It is also known in the prior art to provide solutions that enable end user mobile devices to retrieve content during off-peak periods for later viewing. While such techniques provide advantages, they have not been adapted to content delivery networks.